Substrate compositions and methods for forming semiconductor on insulator devices

Abstract

Methods and apparatus for producing a semiconductor on insulator structure include: subjecting an implantation surface of a donor single crystal semiconductor wafer to an ion implantation process to create an exfoliation layer of the donor semiconductor wafer; bonding the implantation surface of the exfoliation layer to a glass substrate using electrolysis, wherein a liquidus viscosity of the glass substrate is about 100,000 Poise or greater.

The invention claimed is: 
     
       1. A semiconductor on insulator structure, comprising:
 a glass substrate; and 
 a single crystal semiconductor layer bonded through electrolysis to the glass substrate, wherein a composition of the glass substrate is such that a liquidus viscosity thereof is about 100,000 Poise or greater; 
 wherein the glass composition, when calculated in mole percent, and calculated from a batch on an oxide basis, is as follows: 64-72% SiO 2 , 9-16.5% Al 2 O 3 , 0-5% B 2 O 3 , 0.5-7.5% MgO, 1-10% CaO, 0-4.5% SrO, 0-7% BaO, and 0-9% (La 2 O 3 +Y 2 O 3 +RE 2 O 3 ); and 
 wherein RE is a rare earth element, and a sum of MgO, CaO, SrO, BaO, and 3La 2 O 3  divided by Al 2 O 3  in mole percentages is greater than or equal to about 1.10. 
 
     
     
       2. The semiconductor on insulator structure of  claim 1 , wherein a strain point of the glass substrate is greater than about 650° C. 
     
     
       3. The semiconductor on insulator structure of  claim 1 , wherein a strain point of the glass substrate is greater than about 690° C. 
     
     
       4. The semiconductor on insulator structure of  claim 1 , wherein a strain point of the glass substrate is greater than about 710° C. 
     
     
       5. The semiconductor on insulator structure of  claim 1 , wherein the 200 Poise temperature of the glass substrate is below about 1675° C. 
     
     
       6. A semiconductor on insulator structure, comprising:
 a glass substrate; and 
 a single crystal semiconductor layer bonded through electrolysis to the glass substrate, wherein a composition of the glass substrate is such that a liquidus viscosity thereof is about 100,000 Poise or greater; 
 wherein the glass composition, when calculated in mole percent, and calculated from a batch on an oxide basis, is as follows: 64-72% SiO 2 , 9-16.5% Al 2 O 3 , 0-5% B 2 O 3 , 0.5-7.5% MgO, 1-10% CaO, 0-4.5% SrO, 0-7% BaO, and 0-9% (La 2 O 3 +Y 2 O 3 +Re 2 O 3 ), where RE is a rare earth element; and 
 wherein (RO+1.5*RE 2 O 3 )/Al 2 O 3  is between about 0.85 and 1.2. 
 
     
     
       7. The semiconductor on insulator structure of  claim 1 , wherein the Re is a rare earth selected from group consisting of Sc, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and mixtures thereof. 
     
     
       8. The semiconductor on insulator structure of  claim 1 , wherein a composition of the glass substrate includes up to 15%, when calculated in mole percent and calculated from the batch on an oxide basis, of at least one modifying oxide selected from the group consisting of MgO, CaO, SrO, BaO, B 2 O 3 , Ta 2 O 5 , TiO 2 , ZrO 2 , HfO 2 , SnO 2 , P 2 O 5 , ZnO, Sb 2 O 3 , As 2 O 3 , SnO 2  in a total amount not exceeding 20 mole percent. 
     
     
       9. The semiconductor on insulator structure of  claim 1 , wherein the single crystal semiconductor layer is taken from the group consisting of: silicon (Si), germanium-doped silicon (SiGe), silicon carbide (SiC), germanium (Ge), gallium arsenide (GaAs), GaP, and InP. 
     
     
       10. The semiconductor on insulator structure of  claim 1 , wherein:
 the glass substrate includes, in order, a bulk layer, an enhanced positive ion concentration layer, a reduced positive ion concentration layer, where the enhanced positive ion concentration layer contains substantially all modifier positive ions from the reduced positive ion concentration layer as a result of migration; and 
 a conductive or semiconductive oxide layer is located between the reduced positive ion concentration layer of the substrate and the single crystal semiconductor layer. 
 
     
     
       11. The semiconductor on insulator structure of  claim 1 , wherein the single crystal semiconductor layer is bonded through electrolysis to an as-drawn surface of the glass substrate. 
     
     
       12. A method of forming a semiconductor on insulator structure, comprising:
 subjecting an implantation surface of a donor single crystal semiconductor wafer to an ion implantation process to create an exfoliation layer of the donor semiconductor wafer; and 
 bonding the implantation surface of the exfoliation layer to a glass substrate using electrolysis, wherein a liquidus viscosity of the glass substrate is about 100,000 Poise or greater; 
 wherein a composition of the glass substrate when calculated in mole percent, and calculated from a batch on an oxide basis, is as follows: 64-72% SiO 2 , 9-16.5% Al 2 O 3 , 0-5% B 2 O 3 , 0.5-7.5% MgO, 1-10% CaO, 0-4.5% SrO, 0-7% BaO, and 0-9% (La 2 O 3 +Y 2 O 3 +RE 2 O 3 ), where RE is a rare earth element; and 
 wherein a sum of MgO, CaO, SrO, BaO and 3La 2 O 3  divided by Al2O3 in mole percentages is greater than or equal to about 1.10. 
 
     
     
       13. The method of  claim 12 , further comprising:
 separating the exfoliation layer from the donor semiconductor wafer, thereby exposing a cleaved surface of the exfoliation layer; and 
 annealing the exfoliation layer by elevating both the exfoliation layer and the glass substrate to a temperature of at least 700° C. for a period of time to reduce residual ions from the ion implantation step. 
 
     
     
       14. The method of  claim 13 , wherein the annealing step includes elevating both the exfoliation layer and the glass substrate to a temperature of at least 850° C. for a period of time to reduce residual ions from the ion implantation step. 
     
     
       15. The method of  claim 13 , further comprising a further heat treatment process including elevating both the exfoliation layer and the glass substrate to a temperature of at least 1000° C. for a period of time to crystallize the glass substrate. 
     
     
       16. A method of forming a semiconductor on insulator structure, comprising:
 subjecting an implantation surface of a donor single crystal semiconductor wafer to an ion implantation process to create an exfoliation layer of the donor semiconductor wafer; and 
 bonding the implantation surface of the exfoliation layer to a glass substrate using electrolysis, wherein a liquidus viscosity of the glass substrate is about 100,000 Poise or greater; 
 wherein a composition of the glass substrate when calculated in mole percent, and calculated from a batch on an oxide basis, is as follows: 64-72% SiO 2 , 9-16.5% Al 2 O 3 , 0-5% B 2 O 3 , 0.5-7.5% MgO, 1-10% CaO, 0-4.5% SrO, 0-7% BaO, and 0-9% (La 2 O 3 +Y 2 O 3 +RE 2 O 3 ), where RE is a rare earth element; and 
 wherein (RO+1.5*RE 2 O 3 )/Al 2 O 3  is between about 0.85 and 1.2. 
 
     
     
       17. The method of  claim 12 , wherein the Re is a rare earth selected from group consisting of Sc, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and mixtures thereof. 
     
     
       18. The method of  claim 12 , wherein the strain point of the glass substrate is greater than about 650° C. 
     
     
       19. The method of  claim 12 , wherein a strain point of the glass substrate is greater than about 690° C. 
     
     
       20. The method of  claim 12 , wherein a strain point of the glass substrate is greater than about 710° C. 
     
     
       21. The method of  claim 12 , wherein the 200 Poise temperature of the glass substrate is below about 1675° C. 
     
     
       22. The method of  claim 12 , wherein the step of bonding includes:
 heating at least one of the glass substrate and the donor semiconductor wafer; 
 bringing the glass substrate into direct or indirect contact with the donor semiconductor wafer through the exfoliation layer; and 
 applying a voltage potential across the glass substrate and the donor semiconductor wafer to induce the bond. 
 
     
     
       23. The method of  claim 22 , further comprising maintaining the contact, heat, and voltage such that: (i) an oxide layer forms on the substrate between the donor semiconductor wafer and the substrate; and (ii) positive ions of the substrate, including substantially all modifier positive ions, migrate away from the higher voltage potential of the donor semiconductor wafer, forming: (1) a reduced positive ion concentration layer in the substrate adjacent the donor semiconductor wafer; and (2) an enhanced positive ion concentration layer of the substrate adjacent the reduced positive ion concentration layer. 
     
     
       24. The method of  claim 12 , wherein the step of bonding includes bonding the implantation surface of the exfoliation layer to an as-drawn surface of the glass substrate. 
     
     
       25. The method of  claim 12 , wherein the donor semiconductor wafer is taken from the group consisting of: silicon (Si), germanium-doped silicon (SiGe), silicon carbide (SiC), germanium (Ge), gallium arsenide (GaAs), GaP, and InP.